1. Field of the Invention
The compounds of the present invention and the method of their preparation is described in French Patent No. 2,592,042 and U.S. Pat. No. 4,835,172, issued May 30, 1989, the disclosures of which are incorporated herein by reference. Such compounds are described therein as central nervous system activators and as antidepressants.
Some of these compounds have also evinced gastro-motor properties which have formed of U.S. application Ser. No. 450,422 (pending) or anxiolytic and antipsychotic properties which have formed the subject of European Patent Application No. 295,350 and U.S. application Ser. No. 454,015 pending.
It has been discovered that the compounds of formula (I), as defined hereafter are endowed with a specific and completely unexpected property: the improvement of cognitive and memory functions.